Answer:


Explanation:
Hello,
In this case, we can compute the energy by using the following formula for air:

Whereas the moles of air are computed via the ideal gas equation at room temperature inside the 5.5m x 6.5m x 3.0m-room:

Now, we are able to compute heat, by considering that the temperature raise is given in degree Celsius or Kelvins as well:

Finally, we compute the time required for the heating by considering the heating rate and the required heat, shown below:

Regards.
The most important thing to determine whether a change is physical or chemical is whether the substance was changed. When the substance being changed, it is chemical change. Otherwise, it is physical.
Carbon, oxygen, & hydrogen may all be elements found in ethanol, but when separated, they have completely different chemical compounds. They are pure elements where as ethanol is a mixture.